Process for manufacturing nitrogen compounds.



I E. KOCHENDOERFER.

PROCESS FOR MANUFACTURING NITROGEN COMPOUNDS.

APPLICATION FILED MAR. 26. I913.

-Pateni7ed like. 5, 19M.

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PROCESS FOR MANUFACTURING NITROGEN GOMPOUNDS.

Specification of Letters Patent.

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Patented, Dec" 51 It Application filed March 26, 1913. Serial No756,864;

lit has particular relation to the well known cyanization of certaingases, resulting from the carhonization of distillers' wash and thelike, by means of overheating. Said gases have a conside'ahle content ofnitrogen, which renders them very valuable for the manufacture ofnitrogen compounds, such as cyanogen compounds and ammonia.

There are quite a number of processes for such manufacture, but theseprocesses are not sufliciently satisfactory because the yield ofnitrogen compounds is considerably be low that to he expected ontheoretical cal culations. In my U. S. Letters Patent, No. 1,165,358,patented Dec. 21, 1915, entitled Processes for manufacturing nitrogencompounds, I have pointed out in a rather detailed way such gases asresult from the carbonization of distillers Wash and these gases arehereinafter simply called gas es.

In the present state of the art of cyanizing gases generated by thecarhonization of dis-- tillers wash and other like gases by superheating the same, little attention has been paid either to the materialor to the surfaces ofthe channels through which the gases are passed tohe superheated. l have discov cred, however, that in the art ofcyanizing such gases, due attention must be given to the material ofwhich the channels are made and that the economy of the cyanizingprocess is considerably reduced if the surface of the channels is roughand porous. l have furthermore discovered that this injurious effectcaused by'the rough. and porous surfaces of the superheater-channels.mayhe counteracted by increasing the speed of the gases through thechannels in such a way that each of the molecules of gas is in con--tact with the rough and porous surfaces for only a very short time.Finally I have also discovered that the injurious ellects caused lay thecatalytic action of the surfaces of. the

superheaterichannels are more easily avoid ed if. thesupcrheator-channels are made from a material gh ing'an acid reactioniii-- stead of from a material of basic character, although even withmaterial of basic charactor almost theoretical yields of nitrogencompounds may be obtained. it high temperatures and great speed of thegases through the channels are resorted to.

By reason of my invention l have now succeeded in overcoi-ning thewell-known diliiculties of the other processes oi cyanizing gasesprovided the operations are car ried out in the Way described below.

in practising my invention the inside of the channels of a superheaterof any of the well-known constructions is lined with any suitable lireproof material, as for in stance the well known Dims-stones whichconsist chiefly of quarta In selecting this lining material I do notattribute particular importance to the physical condition of saidDinas-stones inasmuch as it is immaterial whether the smoothness oftheir sul. "aces as well as the density of the material. is more or lessperfect. o

In order to counteract the decomposition caused by the rough surfaces aswell as by the porosity of the stones, it is essential to firstestablish the measruements of the crosssection of the channels in Viewof the composition of the distillers wash to he carbonized, and then tofind out that particular speed of the gases which is most 'h'worahle forthe elimination of the decomposing effect of the catalytic action of thesurfaces. The speed of the gases cannot be pcrmanently maintained at thesame rate hut is always subject to the composition or the distillerswash which is known to vary greatly:

I have found it advantageous to pass the gases, which are to he cyaninedand which. contain the nitrogen, mostly in the form of pyridincompounds, through the superheater channels at a speed not exceeding 7meters per second; care must be taken during this operation that thegases at this speed actually attain the high temperaturerequiredcontaining the nitrogen ireferably in the form of aminocompounds may he treated at the same temperature while passing thesuperheater chaimels at a much higher speed, the speed in this casebeing 10 meters and even more per second.

The operations described above otter the further advantage of permittinga direct till lllll passage of the gases from the carbonizer into thesuperheater-channels the gases not sustaining a change in theircomposition during such passage.

Up to the present it has been considered necessary to separate thenitrogenous tar hour the gases on their travel from the carbonizer tothe superheater and to sepa rately cyanize the so-obtained tar; anothermodification of the cyanizing process has consisted in the perfectseparation of the gases into those liable to undergo cyanization andthose not undergoing cyanization.

It is conceded that the two modifications mentioned above really resultin a higher yield of nitrogen compounds, but such yields were stillconsiderably below the theoretical one and are not in proportion to theexpense entailed by carrying out the cumbersome op erations referred to.

The gases undergoing cyanization constitute only a rather small part ofthe gases leaving the carbonizer and though they are accompanied by agreat excess of water vapor and other gases, not undergoing cy anizationand only retarding the reaction, yet 1 am able by my invention toconvert the Lt'hrmer kind of gases into cyanogen compounds and ammoniawith an almost theoretical yield, the more valuable cyanogen compoundshowever, prevailing in the ob tained products to a considerable extent,thus increasing the economical importance of my invention.

The economical results of my process are rather considerable inasmuch asI am able to avoid several cumbersome operations by the practice of mynew process; the improved results-obtained thereby enable me alsoespecially to take advantage of the heat contained in the gases whenleaving the carbonizer and finally to obtain a most satisfactory yieldof cyanogen compounds.

The technical operation of my new process depends a great deal on thecarbonization, which is governed by the composition of the raw materialto be gasilied. If the carbonizcation occurs at a hightemperature anycondensation of compounds may be prevented by carefully insulating theconnection pipes between the carbonizer and the superheater, thisprecaution being assisted favorably by installing connection pipes ofproper dimensions.

In case a raw material is to be gasified which will give the greatestyield of cyanisable gases only when carbonized at a relatively low tenq)eralure, lhe gases and vapors will accordingly be of low temperaturewhen leaving the carbonizer; it is obvious that the operation of thecarbonizer is very important for the regulation of the whole process,for by slackening the lire under the car- 1,. 1* cu. .r i a I. oo izer ican in st Ur ah ieducc the tempera w a r. s v oi. the gases, ii:ecessaiy, and by tnus controlling the fire as pointed out above I canfurthermore also regulate the speed of the gases as required by therelation between the same and the heating surface of the channels. Onthe other side the higher I heat the carbonizer the greater will be thepressure of the gases and consequently also their traveling speed, whileof course a reduction. in the supply of heat will ultimately also reducetheir speed accordingly. If it is advisable that the gases leaving thecarbonizer have a low temperature, the connection pipe between thecarbonixer and superheater must be provided with some suitable meanswhich will permit of immediately heating said pipe sulliciently so as toprevent any segregation of liquids within the pipe. This feature ofpreventing any liquefaction of gases by submitting the same to heat, maybe successfully carried out by using waste heat'lrom the many sourcesexisting in cyanid factories.

F or the further elucidation of my invention a construction of theapparatus preferred for carrying out the process is illustrated, by wayof example, in the accompanying drawing, which is a vertical sectionalview partly diagranunatic of said apparatus. The distillers wash, forexample. is carbonized in the fire clay retorts A and the distillationgases escape through connection pipes B into the main pipe C whence theytravel into a super-heater channel I) surrounded. by a. suitable mantleit made of lire clay bricks or other suitable material. As thesuperheater channel I) is heated to a high temperature, flues'lj ofsuliicient width are interposed between the mantle E and channel D andan inlet G and exit H is pro vided for the heating gases. Thedistillation gases are cyanized while passing through the hotsuperheater channel and leave through exit I to be further treated toassume marketable form.

The process as described is particularly valuable in manufacturingnitrogen com pounds. such as cyanogen compounds and ammonia, and underthe term. nitrogen compounds as used in the claims. I mean to includecyanogen and. ammonia. as well as other compounds coming within thatbroad designation.

What I claim and desire to secure by Letters Patent is:

1. In the process of manufacturing nitrogen compounds from the gasesgenerated by the carlmnization o l" dist-illcrs wash and the likenitrogenous substances, carboni'lziug said substance. superhiating theresulting gases and reducing "the time of contact oi said gases with thesuperl'ieating surface by increasing the speed of said gases over saidsurface.

in the process of manufacturing nitrocompounds from. thegases generatedby carbonization of distillers Wash and like nitrogenous substances,carbonizsaid substance, super-heating the resultgases, reducing thetimeof Contact of the the ing ing said gases with-the supcrheiiitingsurface by increasing the speed of said gases over said surface andvarying said increased speed ing the ratio between the superheating areaand the speed of the gases passing over the same.

the carbonization of distillers wash and the like nitrogenoussubstances, carbonizing the substance, super-heating the resultinggases, controlling the time of'contact of said gases with thesuperheating surface by 'arying the ratio between the superheating areaand the speed of the gases passing over the same and varying said speedaccording to the composition of'said gases.

In testimony whereof I have signed. this specification in. the presenceof two subscribing Witnesses.

ERNST KOCHENDOERFER. \Vitnesses Y HoRs'r ZIEGLER, ALBRECHT TI-IOMA.

Copies of this patent may be obtained for five cents each, byaddressingthe Commissioner of Patents. Washington, D 0.

